Circular, V-couplings for clamping the peripheral end flanges of pipes together have been used for many years, especially in pipes conducting high temperature and pressure fluids. Currently there are many types of V-couplings available for connecting the peripheral end flanges of pipes. One of the more common type coupling is fabricated from sheet metal retainers attached to tension bands. Two examples of these types of pipe couplings are disclosed in U.S. Pat. No. 3,600,770 to Halling and U.S. Pat. No. 4,341,406 to Abbes et al. At first these types of pipe couplings were in widespread use in the aircraft and aerospace industries; however, their reliability was very questionable, owing to failures of their riveted or spot welded joints and fatigue failures of their tension bands.
Another common type of V-coupling was later introduced, using forged, cast or machined retainers, with integrally hinged ends joined by eyebolt fasteners and connecting links. While the "forged-style" couplings have proven extremely reliable and efficient, they suffer from one main disadvantage, which is addressed by the present invention.
Specifically, current "forged-style" couplings use tension-type swing-bolts and connecting links that are disposed at a considerable offset distance from the neutral axis of the coupling retainer channel section. The resultant movement produced by the fastener tightening torque causes inward rotation of the retainer ends which, in turn, locally deflects the flanges of the pipes inward. Opposite the fastener, the two retainers are joined by one or more non-adjustable links, which are offset from the circumferential loading line between the two retainers. This offset arrangement in this type of coupling is essential to the proper functioning of the coupling so that tension is transmitted through the linked retainer ends entirely symmetrically. Accordingly, the same amount of inward deflection occurring at the fastener ends of the retaining member is also produced at the hinged ends of the retaining member.
These problems have led to the development of numerous other types of V-pipe coupling. However, many of these new designs are difficult to manufacture. Moreover, these new designs are often more expensive and complicated to use. One example of a relatively new design is disclosed in U.S. Pat. No. 4,919,453 to Halling et al. While this V-coupling performs quite well, the latch mechanism is more expensive than more conventional latch mechanisms.
Examples of some prior couplings are disclosed in U.S. Pat. No. 1,966,039 to Muchnic; U.S. Pat. No. 3,575,432 to Taylor; and U.S. Pat. No. 3,797,836 to Halling; French Pat. No. 1,403,430 to Avia Equipment Ltd.; and British Pat. Nos. 1,126,872 to Ward et al; and 1,140,636 to Brownhill et al.
In view of the above, it will be apparent to those skilled in the art that there exists a need for a pipe coupling device that reduces distortion of the pipes, and that improves manufacturability of pipe coupling devices. This invention addresses the above needs as well as other needs which will become apparent to those skilled in the art once given this disclosure.